Can you change your video card in a laptop thats a 17 inch if you already have one you just want to upgrade?

Alright so i got an Inspiron 17 with 4gb ddr3, an i5 prossesor, and a 512 ATI mobility Radeon HD video card. i know my card is weak and i was just wondering if i could upgrade my video card to a nicer one preferably with 1gb later on? or do i need to bring it to a local computer store?Can you change your video card in a laptop thats a 17 inch if you already have one you just want to upgrade?The graphic card in laptops is soldered to the motherboard during the manufacturing phase. It makes it virtually impossible to upgrade the graphic card in a laptop.